Light controls nanoscale bubble domains in ferroelectric crystal, Flinders study finds

Researchers at Flinders University report that light can control nanoscale bubble domains inside a ferroelectric crystal, with the largest change arriving after illumination stops, according to a phys.org write-up of a study in Advanced Functional Materials. Dr. Pankaj Sharma said the team found light can control bubble domains about a few billionths of a meter across in a special ferroelectric crystal, and that unlike most materials that respond while light shines, the biggest change happened after the light was switched off. Postdoctoral fellow Dr. Haoze Zhang led the study in the Sharma group at Flinders University's College of Science and Engineering. Nanodomains responded only slightly under near-visible light, then expanded rapidly when light was removed, temporarily switching the electronic state of the crystal surface before it gradually returned. Collaborators from UNSW Sydney, India, and the U.S. used advanced microscopy and electrical measurements to track charges. Electrons accumulate near the surface while light is on and are suddenly released when light is removed, triggering rapid switching, with caption data noting a surface potential jump of about -5 V on a PMN-xPT crystal. Zhang said the after-light switching behavior could reduce energy use and unwanted heating versus conventional light-controlled devices. The paper is listed as Effect of Optical Illumination on Bubble Nanodomains, DOI: 10.1002/adfm.77010.